Seven minutes. That’s all the time children need each day engaging in “vigorous” physical activity to stay healthy. But most kids aren’t getting even that much, new research shows.
The findings come from a study led by University of Alberta medical scientists who sought to determine how much exercise children need each day and how much most actually get.
"If you watch late-night television, or look in the backs of magazines, you'll see magical ads saying you need just 10 minutes a day or five minutes a day of exercise to stay fit,” noted researcher Richard Lewanczuk, with the Faculty of Medicine & Dentistry at the U of A. “And for those of us in the medical field, we just rolled our eyes at that. But surprisingly, they may actually be right and that's what this research shows."
In findings published in the journal Archives of Pediatrics & Adolescent Medicine, Lewanczuk researchers studies found kids don’t need “a lot of intense physical activity to get the health benefits of exercise” — just seven minutes or more of high-intensity activity is all that’s required.
“But the seven minutes had to be intense to prevent weight gain, obesity and its adverse health consequences,” he said. “And most kids weren't getting that."
For the study, researchers evaluated the health of more than 600 children, between the ages of 9 and 17, who wore monitors that tracked their physical activity levels for seven days. They also had their weight, waist size, and blood pressure regularly monitored.
Researchers found the children spent almost 70 percent of their time doing sedentary activities; nearly 23 percent was devoted to light physical activity; almost seven percent to moderate physical activity and 0.6 percent to vigorous physical activity.
But the more vigorous the physical activity children engaged in, the less likely they were to be overweight. The study also showed children who were overweight were able to boost their fitness levels and shrink their waist lines by increasing the amount of time spent doing vigorous activities.
Lewanczuk said colleagues also found children who engaged in only mild or moderate activity didn’t experience significant health benefits. But kids who took part in vigorous physical activity that lasted longer than seven minutes had significantly better health benefits.
"This research tells us that a brisk walk isn't good enough" for children, said Lewanczuk. "Kids have to get out and do a high-intensity activity in addition to maintaining a background of mild to moderate activity. There's a strong correlation between obesity, fitness and activity. Activity and fitness is linked to a reduction in obesity and good health outcomes."